There is a hidden message embedded within the below image just below the graphic of Shadow the Hedgehog that cannot be viewed using a normal image viewer. Can you find it?
Hint 1:
To find it, you need to use pyrotechnics.
Hint 2:
The message is written in one specific font and begins with "I'm".
I'm looking for an answer that also clearly explains the trick I used to obscure the text and why it works. Bonus points for finding the user being referred to by the image.